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  <title>Document</title>
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  <script>
    // > < >= <=

  
    // == === =

    // 1. =  赋值
    // var num = 123

    // 2. == 比较 是否相等
    // console.log( 123 == 456 )  // false
    // console.log( 123 == 123 )  // true
    // console.log( 123 == '123' )  // true


    // 3. === 比较 是否想等     即比较数据，又比较类型
    // console.log( 123 === 456 )  // false
    // console.log( 123 === 123 )  // true
    // console.log( 123 === '123' )  // false

    // !=   !==

    console.log('qwer' !== '123')  // true


  </script>
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